A DevOps Engineer Wants to Prevent Developers from Pushing Updates

A DevOps Engineer wants to prevent Developers from pushing updates directly to the company's master branch in AWS CodeCommit. These updates should be approved before they are merged. Which solution will meet these requirements?

A) Configure an IAM role for the Developers with access to CodeCommit and an explicit deny for write actions when the reference is the master. Allow Developers to use feature branches and create a pull request when a feature is complete. Allow an approver to use CodeCommit to view the changes and approve the pull requests.
B) Configure an IAM role for the Developers to use feature branches and create a pull request when a feature is complete. Allow CodeCommit to test all code in the feature branches, and dynamically modify the IAM role to allow merging the feature branches into the master. Allow an approver to use CodeCommit to view the changes and approve the pull requests.
C) Configure an IAM role for the Developers to use feature branches and create a pull request when a feature is complete. Allow CodeCommit to test all code in the feature branches, and issue a new AWS Security Token Service (STS) token allowing a one-time API call to merge the feature branches into the master. Allow an approver to use CodeCommit to view the changes and approve the pull requests.
D) Configure an IAM role for the Developers with access to CodeCommit and attach an access policy to the CodeCommit repository that denies the Developers role access when the reference is master. Allow Developers to use feature branches and create a pull request when a feature is complete. Allow an approver to use CodeCommit to view the changes and approve the pull requests.