Fact Pattern 11-5 Dex and Carmen Are in an Auto Accident

Multiple Choice

Fact Pattern 11-5 Dex and Carmen are in an auto accident. Dex offers Carmen $2,000 if she promises not to pursue her potential legal claim against Dex. Carmen agrees. Later, Carmen discovers that it will cost $1,500 to repair her car and $4,000 to cover the medical expenses for a latent injury.
-Refer to Fact Pattern 11-5.The agreement between Dex and Carmen is​ 

A)  ​a covenant not to sue. 
B)  ​an illusory promise. 
C)  ​a release. 
D)  ​promissory estoppel.