Given below are two statements: $\\$ Assertion (A) : All vertebrates are chordates but all chordates are not vertebrate. $\\$ Reason (R) : The members of subphylum vertebrata possess notochord during the embryonic period, the notochord is replaced by cartilaginous or bony vertebral column in adults. $\\$In the light of the above statements, choose the correct answer from the options given below: