Interpret “from 0 to 100†as the spelled-out English names:
\(\text{zero, one, two, }\ldots,\text{ ninety-nine, one hundred}\).
There is no letter `a' in any of these words (up to \(100\) inclusive) unless one uses “and†(e.g., “one hundred and oneâ€), which is not within 0–100. Hence the count is \(0\), which is not in options (a)–(c).
\[
\boxed{\text{Answer: None of these}}
\]