A lahar is produced when:.a) ash is blown out of a vent and onto the side of the volcanob) ash and other pyroclastic ejecta become saturated with waterc) a lateral blast spreads ash across a large aread) a lava flow breaks apart on the steep portion of a composite cone

ash and other pyroclastic ejecta become saturated with water

Explanation:

Lahars occur more commonly after a landscape has been covered by loose volcanic material, Lahars pick up material as they travel, which can cause damage to structures in their path.

A muddy mass of quickly moving volcanic fragments. Lahars usually contain ash, breccia, and boulders mixed with rainwater, or river or lake water formed by the volcano-related lava flow. The deposit that such a flowing mass produces is known as Lahar.

B. Ash and other pyroclastic ejecta becames saturated with water.

Explanation: Pyroclastic flows can generate lahars when very hot, flowing rock debris erodes and mixes with and melts ice and show as it travel rapidly down steep slopes. It can also be formed when high-volume or long-duration rainfall occurs during or after an eruption.