Question

What are the most commonly used active filters?

(a) All of the mentioned

(b) Low pass and High pass filters

(c) Band pass and Band reject filters

(d) All-pass filters

This question was addressed to me at a job interview.

My question comes from Active Filters in section Active Filters of Linear Integrated Circuits

Answer 1

Right option is (a) All of the mentioned

Illuminate the topic with: All the mentioned filters use op-amp as active element and capacitors & resistors as passive elements.