Which missing item would complete this beta decay reaction?

We know that the mass number (top number) must be 33 because the electron that is emitted has no mass. The atomic number (bottom number) must be 15, because it is one less than 16 and the electron has a negative charge. Therefore, the first box is the answer.

Wyyeurudydudyeye2y3y3y3ueuudisusuisus7w7uwh2u

Answerd. may include all of these are many definitions of bases: the  brønsted-lowry definition of acids and bases says that bases are proton acceptors.the arrhenius definition of acids and bases says that bases increase [oh⁻] in solution (thereby producing oh⁻ ions)the lewis definition of acids and bases says that bases donate electron pairs.therefore, the sensible answer is that a base may include all of the described characteristics.