To find the regular cost per month (m), we start with the total cost for the 12-month membership after applying the discount.
The total cost without the discount would be \(12m\). Since Spencer received a one-time discount of $35, the equation representing the total amount paid after applying the discount would be:
\[ 12m - 35 = 205 \]
So, the correct equation Spencer can use to find \(m\) is:
A. \(12m - 35 = 205\).