Traditional musical instruments often used in Sikkimese folk songs include:

Damphu (drum)
Tungna (string instrument)
Flute
All of the above

The correct answer is: d) All of the above

The damphu is a traditional drum used in Sikkimese folk music. It is made of wood and has a skin stretched over one end. The damphu is played by striking the skin with the hands or with a stick.

The tungna is a traditional string instrument used in Sikkimese folk music. It is made of wood and has two strings. The tungna is played by plucking the strings with the fingers.

The flute is a traditional wind instrument used in Sikkimese folk music. It is made of wood or bamboo and has six holes. The flute is played by blowing into the mouthpiece and covering the holes with the fingers.

All of these instruments are used in a variety of Sikkimese folk songs. They are played to accompany dances, to tell stories, and to celebrate special occasions.