Final answer:
VFR aircraft are not required to have a clearance to enter Class G airspace, but entry may be denied due to restrictions or congestion.
Step-by-step explanation:
In Aviation, VFR (Visual Flight Rules) aircraft are not required to have a clearance to enter Class G airspace. However, entry into Class G airspace may be denied due to certain restrictions or airspace congestion. Class G airspace is uncontrolled and typically exists below certain altitudes, primarily in rural areas.