What Condition Is Considered Sufficient for an Interstellar Cloud to Collapse

question 174

Multiple Choice

What condition is considered sufficient for an interstellar cloud to collapse and form a star or stars (i.e., if this condition holds then the cloud has to collapse) ?

• A) The cloud must be alone in space (far from stars and other interstellar clouds).
• B) Gravity must dominate gas pressure inside the cloud.
• C) Gravity must be strong enough to reach all parts of the cloud.
• D) The cloud must be cooler than 100 K.