The correct answer is option 4: A is false but R is true. Here`s why:

In the given assertion, it is claimed that red light is more energetic than green light in the visible spectrum. In reality, the energy of light is inversely proportional to its wavelength. Given that red light has a longer wavelength than green light, it actually has less energy, not more. Hence, Assertion A is false.

The reason provided is that the wavelength of red light is more than that of green light. This is indeed true. Red light has a longer wavelength in comparison to green light in the visible light spectrum.

So, dissecting each option:

Option 1 is incorrect because although both statements are individually true, the reason is not the correct explanation for the assertion.

Option 2 is incorrect because the reason provided is not the correct explanation for the assertion.

Option 3 is incorrect because the assertion is false but the reason is true.

Option 4 is correct because the assertion made is false, whereas the reason is true.