Write hydrocarbon radicals that can be formed

Write hydrocarbon radicals that can be formed as intermediates during monochlorination of 2-methylpropane. Which of them is more stable? Give reasons.

2-methylpropane gives two types of radicals.

Radical (I) is more stable because it is 3° and stabilised by nine hyperconjugative structures (as it has 9 CC-hydrogens).
Radical (II) is less stable because it is 1 ° and stabilised by only one hyperconjugative structure (as it has only 1 a-hydrogen).