PG TRB Model Question Papers with Answer 2020-21 - 3

Question: 11

Which of the following can be used for biological control of mosquitoes?

(A) Gambusia

(B) Oil

(C) DDT

(D) Gamaxene

Question: 12

Which is the strongest acid?

(A) Carbonic acid (H₂CO₃)

(B) Hydrochloric acid (HCL)

(C) Sulphuric acid (H₂SO₄)

(D) Nitric acid (HNO₃)

Question: 13

Which of the following pairs is not correctly matched?

(A) Acetylene – used in welding of metals

(B) Alkanes – useful for manufacture of dyes

(C) Carbohydrate – essential for body growth

(D) Urea – useful as a fertiliser

Question: 14

Which of the following is a non conventional source of energy?

(A) Biogas

(B) Coal

(C) Oil

(D) None of these

Question: 15

Which of the following substances is a polymer of isoprene?

(A) Bakelite

(B) Melamine

(C) Thiokol

(D) Natural rubber