The correct answer is Missing Work On Issues permission.

The Work On Issues permission controls whether a user can perform active work on issues in the project and that includes the ability to log work when time tracking is enabled. If Lena lacks the Work On Issues permission she will not see controls to record time even though the issue has an estimated duration.

Missing Edit Own Worklogs permission is not correct because that permission only controls the ability to modify worklog entries that the user has already created and it does not prevent the user from creating new worklogs.

Time tracking disabled in global settings is not correct because if global time tracking were disabled there would generally be no estimated durations or log work interface visible on the issue. The presence of an estimated duration implies time tracking is enabled.

Missing Schedule Issues permission is not correct because that permission governs scheduling fields such as start and due dates and it does not control the ability to log work on an issue.

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