In-process quality control (IPQC) means the checks a tablet press operator runs at intervals while the batch is still being compressed, so that a problem is caught and corrected before thousands of bad tablets are made. Finished-product tests, on the other hand, are run once compression is complete and the batch is ready for release.
Weight variation, hardness, and friability all fall in the first group. A sample of tablets is pulled from the hopper output every 15-30 minutes, weighed, checked on a hardness tester, and tumbled in a friabilator. These three results tell the operator in real time whether the punch pressure, powder flow, or die fill needs adjusting.
Zeta-sizing belongs to nanoparticle characterisation, not tablets. Drug content assay and dissolution both need a finished, often coated, tablet and standard analytical methods that take longer than a quick in-line check, so they are done on the completed batch as release tests. Puncture test applies to films and soft capsules, not compressed tablets.
So the option that lists only true in-process checks is hardness, friability, and average weight, and that is the correct answer.