NEET 1991 · Class 12

Principles of Inheritance and Variation

Freshly released human egg has

  1. (A)one Y-chromosome
  2. (B)one X-chromosome
  3. (C)two X-chromosome
  4. (D)one X-chromosome and one Y-chromosome.

The NCERT line that answers it

Verbatim line

Females, however, produce only one type of ovum with an X-chromosome.

Chapter
Principles of Inheritance and Variation
Section
4.6.1 Sex Determination in Humans
Page
20
Words matched
11 of 11

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

5, emb=1.0, combined=0.8). Verified: high — The span 'Females, however, produce only one type of ovum with an X-chromosome' directly states that human eggs (ova) contain exactly one X-chromosome, which matches option B and distinguishes it from all other options.

We did this for 1,565 questions.

Every one traced to the exact sentence in NCERT that answers it, including 90% of the 2026 paper. Sit a mock on the real NEET 2027 computer interface and every mark you drop comes back with its line attached.

Take the free 5-minute checkMore from this chapter

Question text is reproduced from the published NEET 1991 paper for study and commentary. NCERT text is quoted, not redistributed; textbooks remain at ncert.nic.in. Our mapping method, including its measured error rates, is published at /methodology.