The pattern given is
A C E G
We need to find the next letter in the sequence.
Look at the image below that dissects the sequence:
First letter in the sequence is "A"
we drop the next letter, "B".
Second letter in the sequence is "C"
we drop the next letter, "D".
This is how the sequence progresses.
This way, the next letter of the sequence would be "I".
The sequence is:
A C E G I
