Question SPL - Sailplane Pilot License - Meteorology

What change in thermal activity may be expected with cirrus clouds coming up from one direction and becoming more dense, blocking the sun? - SPL

Cirrus clouds may intensify insolation and improve thermal activity

Cirrus clouds indicate an high-level inversion with thermal activity ongoing up to that level

Cirrus clouds prevent insolation and impair thermal activity.

Cirrus clouds indicate instability and beginning of over-development