Find examples of C-H bond dissociation energies in Table 10.1 that are as closely related as possible

Question:

Find examples of C-H bond dissociation energies in Table 10.1 that are as closely related as possible to the bonds to Ha, Hb, and Hc in the molecule at right. Use these values to answer the questions below.
(a) What can you conclude about the relative ease of radical halogenation at Ha?
(b) Comparing Hb and Hc, which would more readily undergo substitution by radical halogenation?