What observational factor is cited as a critical driver for the intense mass outflow during the AGB phase?

Answer

Stellar pulsations.

Observations suggest that as stars on the AGB begin to pulsate in certain modes, particularly corresponding to specific periods, the rate of mass loss significantly increases, aided by the subsequent formation of dust dragging material outward.

What observational factor is cited as a critical driver for the intense mass outflow during the AGB phase?
starradiationmassevidencestellar wind