Which are the constant (ACHAL) swar?

Correct option is B

The correct answer is SA–PA
In Indian classical music, the seven basic swars (musical notes) are: Sa, Re, Ga, Ma, Pa, Dha, Ni. Among these, Sa (Shadja) and Pa (Pancham) are considered Achal Swar, which means fixed or immovable notes. Their pitch does not change, and they do not have a Komal (flat) or Tivra (sharp) form.
· Achal swars: SA and PA
· Chal swars: RE, GA, MA, DHA, NI
· These can exist in Komal (flat) or Tivra (sharp) forms, except MA, which only has a Tivra form.
These Achal swars serve as the foundation in any raag and remain constant in pitch, making them stable references for tuning instruments and vocal practice.
Information Booster:
· The harmonium or tanpura is usually tuned based on Sa and Pa.
· Sa is considered the reference note (tonic), and Pa is the perfect fifth to Sa.
· These notes are always shuddh (natural) and form the skeleton of all raags.
Additional Knowledge:
· SA–GA: GA is a Chal swar; it has both shuddh and komal versions.
· SA–MA: MA is a Chal swar; it can be Shuddh or Tivra.
· SA–DHA: DHA is also a Chal swar; it can be Shuddh or Komal.