Explain the options please

Just check this video out https://www.youtube.com/watch?v=ThACX_Mn4_Y&t=101s

If you don't know the meaning of monotonic functions it just means means the function moves in only one direction, it never reverses its trend.

Monotonically Increasing: As x increases, y never decreases. It either goes up or stays flat. In this case The first derivative is non-negative (f'(x)≥0).

Monotonically Decreasing: As x increases, y never increases. It either goes down or stays flat. In this case The first derivative is non-positive (f′(x)≤0)