A 7 year old patient has a Angle Class I dental and skeletal relationship. Tooth 6.1 is retained and not mobile. Tooth 2.1 is fully erupted and in lingual crossbite. The most appropriate management for this patient is

extract tooth 6.1 and use a Hawley retainer with
finger springs.

extract tooth 6.1 and recommend the use of a
tongue depressor.

extract tooth 6.1 and observe.

wait for exfoliation of tooth 6.1.