Answer:
A and C
Step-by-step explanation:
Helioseismology is a branch of science that makes use of differential rotation and magnetic field to study he structure of the sun.
A filtergram represents the photo of the surface of the sun that is made using high energy particles being accelerated by the sun's magnetic field. Hence, it can only be used to study the surface and not the layers below the photosphere.
The chromosphere of the sun has a temperature between 6,000 °C to about 20,000°C while the photosphere has a temperature between 4,230 and 5,730 °C. Hence, the chromosphere has a higher temperature.
The only true options are A and C.