41.
Assertion: the apex of a V formed by a bed crossing a valley points in the dip direction. Reason: the outcrop is deflected upstream where the bed descends.
Answer: A
Correct answer: both the assertion and the reason are true and the reason explains the assertion
Both are true and the reason gives the mechanism. Where a bed dips, its outcrop stands at a lower position in the valley floor than on the interfluves on either side, so the trace swings up the valley and closes to an apex pointing down dip. The rule fails only where the dip is gentler than the stream gradient, in which case the V reverses.
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