ACCA has recently use on-screen marking to grade the papers. Answer scripts are scanned and digitalised. The electronic version of the scripts is then sent to the markers for grading. Therefore, to ensure that the answers are scanned into the computers, a black ballpoint pen is needed. Further care is needed by not writing the answers out of the margins provided.
That is what is said by my lecturer. Oh gosh, and he recommended 0.7mm as the preferred size. It is a double assurance that the words written will be picked up. Sigh… Time to change pen. Again.