🩺 Why Do We Fall Ill – Class 9 Science MCQs

Section 4: Social Aspects, Nutrition, Prevention & HOTS (Q76–Q100)

Q76. Which factor does NOT directly affect individual health?

A. Balanced diet
B. Clean surroundings
C. Literacy
D. Color of clothes

✅ Correct Answer: D. Color of clothes

Explanation:

• Health is affected by nutrition, sanitation, education, but not clothes’ color.

Q77. Which is a social factor affecting health?

A. Income level
B. Gender equality
C. Public hygiene
D. All of these

✅ Correct Answer: D. All of these

Q78. Community health depends on:

A. Clean water supply
B. Good sewage disposal
C. Vaccination programmes
D. All of these

✅ Correct Answer: D. All of these

Q79. Deficiency of which vitamin causes night blindness?

A. Vitamin A
B. Vitamin B1
C. Vitamin C
D. Vitamin D

✅ Correct Answer: A. Vitamin A

Q80. Deficiency of vitamin D causes:

A. Scurvy
B. Rickets
C. Beriberi
D. Pellagra

✅ Correct Answer: B. Rickets

Q81. Which mineral deficiency causes anaemia?

A. Calcium
B. Iron
C. Iodine
D. Potassium

✅ Correct Answer: B. Iron

Q82. Goitre is caused by deficiency of:

A. Iron
B. Iodine
C. Calcium
D. Vitamin A

✅ Correct Answer: B. Iodine

Q83. Which of these is NOT a deficiency disease?

A. Scurvy
B. Beriberi
C. Tuberculosis
D. Rickets

✅ Correct Answer: C. Tuberculosis

Q84. Which nutrient deficiency causes scurvy?

A. Vitamin A
B. Vitamin B1
C. Vitamin C
D. Vitamin D

✅ Correct Answer: C. Vitamin C

Q85. Pellagra is caused by deficiency of:

A. Niacin (Vitamin B3)
B. Vitamin B1
C. Vitamin B12
D. Vitamin K

✅ Correct Answer: A. Niacin (Vitamin B3)

Q86. Kwashiorkor is caused by deficiency of:

A. Protein
B. Carbohydrate
C. Fat
D. Vitamin

✅ Correct Answer: A. Protein

Q87. Which of these is a protein-energy malnutrition disease?

A. Kwashiorkor
B. Marasmus
C. Both A and B
D. Pellagra

✅ Correct Answer: C. Both A and B

Q88. Marasmus is caused by deficiency of:

A. Vitamin D
B. Protein + calories
C. Iron
D. Iodine

✅ Correct Answer: B. Protein + calories

Q89. Which is an example of non-communicable disease?

A. Diabetes
B. Typhoid
C. Malaria
D. Cholera

✅ Correct Answer: A. Diabetes

Q90. Which disease is called “lifestyle disease”?

A. Malaria
B. TB
C. Hypertension
D. Typhoid

✅ Correct Answer: C. Hypertension

Q91. Vaccination helps because:

A. Kills germs directly
B. Provides pre-formed antibodies
C. Develops memory cells against germs
D. Gives nutrition

✅ Correct Answer: C. Develops memory cells against germs

Q92. Which of these is an example of vector-borne disease?

A. Typhoid
B. Malaria
C. TB
D. Cholera

✅ Correct Answer: B. Malaria

Q93. Which of these is the MOST effective step for controlling infectious diseases?

A. Good food
B. Good clothes
C. Public hygiene and sanitation
D. Taking painkillers

✅ Correct Answer: C. Public hygiene and sanitation

Q94. Which of these is NOT a mode of prevention?

A. Proper nutrition
B. Vaccination
C. Antibiotics
D. Sanitation

✅ Correct Answer: C. Antibiotics

Explanation:

• Antibiotics treat diseases, not prevent them.

Q95. Which of these spreads through unsafe blood transfusion?

A. AIDS
B. Dengue
C. Cholera
D. Malaria

✅ Correct Answer: A. AIDS

Q96. Which of these is NOT an infectious disease?

A. Cancer
B. AIDS
C. Malaria
D. Cholera

✅ Correct Answer: A. Cancer

Q97. Which of these is NOT caused by microorganisms?

A. Diabetes
B. Cholera
C. Influenza
D. TB

✅ Correct Answer: A. Diabetes

Q98. Which one is an example of genetic disease?

A. Malaria
B. Typhoid
C. Haemophilia
D. TB

✅ Correct Answer: C. Haemophilia

Q99. Which one is NOT a principle of public health?

A. Clean water supply
B. Proper sewage disposal
C. Vaccination programmes
D. Providing free clothes

✅ Correct Answer: D. Providing free clothes

Q100. Which statement is correct about prevention of diseases?

A. Prevention is better than cure
B. Treatment is always better
C. Prevention is impossible
D. Only medicines work

✅ Correct Answer: A. Prevention is better than cure

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