The answer must be option A. My take :
The area of a triangle is 0.5 * base * height. Now we need to compare the areas of ABD and BDC.
The area of ABD is 0.5*AD*h.
The area of BDC is 0.5*CD*h.
To compare the area of ABD and BDC, we need to know the relation between AD and CD.
Option A - Sufficient
Option B - Not sufficient.
Hence option A is the answer.
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