Which among the following was/were the shell-based production centre(s

Which among the following was/were the shell-based production centre(s) of the Indus Valley Civilization ?

Shortughai
Lothal
Balakot and Nageshwar
Allahdino and Dholavira
This question was previously asked in
UPSC CISF-AC-EXE – 2021
Balakot and Nageshwar were well-known specialized centres for shell working during the Indus Valley Civilization period due to their coastal location.
– Coastal settlements of the Harappan Civilization often specialized in crafts utilizing marine resources like shells.
– Shell objects such as bangles, beads, inlay, and ladles were produced in large quantities at these sites.
Lothal was a major port city and manufacturing centre, including bead making and metallurgy, but Balakot and Nageshwar are particularly renowned for shell-based industries. Shortughai (in Afghanistan) was important for Lapis Lazuli. Dholavira was a major urban centre with diverse crafts, and Allahdino was a coastal settlement with craft production, but Balakot and Nageshwar are most directly identified as primary shell production centres.