To screen calls, you can use apps like:
Phone by Google;
Truecaller;
CallApp;
Mr. Number.
In a business phone system, the IVR can screen your calls. Most of the bots will not be able to follow the instructions given by IVR to get connected to your sales reps. Call screening helps:
Avoid spam calls;
Reduce call abandonment rate;
Have fewer missed calls;
Improve productivity.