Remark
I'm going to assume you are in the Northern Hemisphere.
Answer
A looks like you are beginning in Winter. The temperature is down quite a bit. That would be about October where I live. B is spring because the temperature is rising but not at it's peak. That would be about April May here.
C is summer. Glorious warm summer. June July and August.
D is autumn. The temperature is falling and it is just about at it's low peak again.
