Which of the following enzymes is used to modify red blood cells for use in blood grouping and crossmatching tests?

A Papain ✓
B Bromelain
C Ficin
D Trypsin

Explanation

Papain is an enzyme that is used to modify red blood cells, making them more reactive with certain antibodies, which is useful in blood grouping and crossmatching tests.

Source

Blood Bank Manual
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Easy MEDICAL Confidence: high