Answer:
Only options A and B are correct, i.e. y = sin∅ and y = cos∅.
Explanation:
The graphs that oscillate, should be periodic in nature and continuous functions.
We know all trigonometric functions are periodic in nature. But not all trigonometric functions are continuous.
The function is continuous if its values are defined at all angles and it should not be undefined for any particular angle.
We know the following facts:-
tan(90°) = ∞
sec(90°) = ∞
csc(0°) = ∞
cot(0°) = ∞
Only sin and cos don't have values ∞ at any angle. It means only sin and cos are continuous functions.
Hence, only options A and B are correct, i.e. y = sin∅ and y = cos∅.