Answer : D
The given language is Regular and Every regular language satisfies the Pumping lemma for Regular languages. So, $a$ is True and $r$ is false.
Simple RegEx for All strings not containing the substring 101: $0^* (1^*000^* )^*1^* 0^*$
Notice that a $1$ may be followed by either a $1$ or by a $00$, and this pattern can be repeated as many times as we want. This pattern is expressed in $(1^*000^* )^* $. The extreme cases where a string can start or end with $0's$ or contain only $1's$ are covered by the expressions left and right from the pattern $(1^*000^* )^*$ .