Inattentive students would write TAILS. This answer is not cor | The INTELLECTUALS

Inattentive students would write TAILS. This answer is not correct though.
The question asks about Embryo (singular) and Its part of the body (singular too).
The text, however, describes how Embryos (plural) move their Tails (plural as well).
For this reason, the correct answer is TAIL (even if it's written differently in the passage).
Source: Road to IELTS, British Council
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