Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. In the light of the above statements choose the correct answer from the options given below.
- A is true but R is false.
- A is false but R is true
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is NOT the correct explanation of A.
Answer
(1) A is true but R is false.
Solution
Assertion: Members of subphylum Vertebrata possess a notochord during the embryonic period, which is replaced by a cartilaginous or bony vertebral column in the adult. True.
Reason: Since every vertebrate is a chordate but protochordates (urochordates, cephalochordates) are not vertebrates, the correct statement is “all vertebrates are chordates but all chordates are not vertebrates”. The Reason states the reverse, so it is false.
Answer: (1)