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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