The correct answer is:
37/20Ca --> 37/19K + 0/+1e
Step-by-step explanation:
Transmutation, conversion of 1 element into another. A transmutation entails an amendment within the structure of atomic nuclei and thus is also induced by an action (q.v.), like nucleon capture, or occur ad libitum by decay, like disintegration and disintegration(qq.v.)