Ground-based radio telescopes can collect data from distant objects in space

a.

during the night only and in clear weather only.

b.

during the day or night and in any weather conditions.

c.

during the day or night and in clear weather only.

d.

during the night only and in any weather conditions.

Ground-based radio telescopes can collect data from distant objects in space  during the day or night and in MANY different weather conditions.

BUT ...

-- of course, they have to avoid pointing at the Sun, since the Sun is a loud, humongous source of radio signals !

-- of course, they have to shut down during lightning storms and most rain, because lightning is a loud, humongous source of radio signals, and rain can generate radio static noise.  Rain can also create puddles and unsymmetric wetting inside the radio "dish" antenna, which really messes up the gain and directional pattern of the antenna.    

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.