In which of the following case of mixing of a strong acid with strong base (each of 1N concentration), temperature increase will be the highest?

• 30 c.c acid and 30 c.c base.
• 20 c.c acid and 25 c.c base.
• 15 c.c acid and 35 c.c base.
• 35 c.c acid and 15 c.c base.