What is indicated to a QoS AP when a QoS STA sets U-APSD Flag bits to 1 in Association and Reassociation frames?

A.
Which access categories are both trigger- and delivery-enabled.

B.
The maximum number of data frames that should be queued by the QoS AP for that QoS STA.

C.
The number of TXOPs that are requested by this QoS STA.

D.
Which user priorities are mapped to access categories.

E.
Which access categories are scheduled.