Correct option (a)
Explanation:
Two diameters are said to be conjucgate when each bisects all chords parallel to the other.
Conjugate diameters are diameters passing through centre and product of their slopes is equal to -b2/a2
Area of parallelogram = 4 area of parallelogram
QDCE = 4 (2 area of ΔCDE)
= 4 (abcos2α + absin2α)
= 4 ab
= (2a)×(2b)
= Product of the axes of ellipse