Assertion :Presence of xylem vessels is a primitive character. Reason: Xylem vessels are present in some Pteridophytes like Selaginella.

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

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Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.

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Assertion is correct but Reason is incorrect.

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Both Assertion and Reason are incorrect.

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Solution

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
Angiospermic xylem is composed by vessels, tracheids, fibres and parenchyma. Xylem in pteridophytes and gymnosperms has tracheids and parenchyma but lack vessels. Vessels are derived from tracheid like cells which have bordered pits at their tapering end walls. Dissolution of cross walls of these pits leads to differentiation of a tracheid cell into vessel. Thus, presence of vessels is an advanced character. A vestigial trait is defined as an attributes that have apparently lost most or all of their function as were exhibited by ancestral species but is maintained through evolution and xylem vessels are fully functional tissues.
Thus, the correct answer is option B.

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