Answer:
b.Only type V detects this light.
Explanation:
This is because, the first vertical polarizer reduces the intensity of the light by half. This is because only the vertically polarized light is let through, while the rest it blocked.
Now if the second polarizer was placed in any angle that was not vertical, the intensity of the light would have decreased even more so than half of the original intensity. Since this is not the case, the second polarizer is also placed with its transmission axis vertical.
This means that the light coming out the second polarizer is also vertically polarized like before.
Thus, only the type V cell will detect this light.