Answer
See the answer below.
Work Step by Step
Na: Group 1, period 3
Al: Group 13, period 3
B: Group 13, period 2
C: Group 14, period 2
a) Na, atomic radius is bigger in later periods and earlier groups.
b) C, the negative of the electron attachment energy is greater in later groups and earlier periods
c) $Na\lt Al \lt B\lt C$, ionization energy is greater in later groups and earlier periods.