Which of the following could explain why the builds are waiting in the build queue?

A Freestyle job is configured to execute concurrent builds, and to only build on a specific agent (agent A) that has 4 executors. You observe that 2 Instances of the job are currently building while several others are waiting in the build queue.

Which of the following could explain why the builds are waiting in the build queue?

A. There are not enough idle executors available on agent A.

B. Changes were made to this job’s configuration while this Job had builds in the build queue.

C. Each build in the build queue must be manually attached to an available executor.

D. The "Execute concurrent builds if necessary option in the job configuration has reached Its user-defined maximum.

Answer: A