In DC$-$DC converter control loop design, the open loop DC Gain of the converter

$($a$)$ should be as stable as possible

$($b$)$ should be as accurate as possible

$($c$)$ should be'as high as possible

$($d$)$ should be as constant as possible

Could you provide an explaination as to why the particular answer was chosen, in addition to this, could you also provide with the following answers and explaination for the following gain types

Close loop DC gain

Open loop AC gain

Close loop AC gain

Voltage gain

Current gain

Proportional gain

Integral gain

Derivarice gain

Loop gain

Power gain

Phase gain