Change the following from active to passive:
The chief scientist is believed to have been coordinating cross-lab efforts since the early stages of the project.

Correct option is C

The correct passive voice of the given sentence is (c).
Explanation: The underlying active idea is: People believe that the chief scientist has been coordinating cross-lab efforts since…
· To make cross-lab efforts the subject and keep the belief construction plus the present perfect continuous aspect, we need:
· are believed (present simple passive of believe for plural subject) + to have been being coordinated (perfect continuous passive) + by the chief scientist + time adjunct.
· Hence: “Cross-lab efforts are believed to have been being coordinated by the chief scientist since the early stages of the project.”
· This preserves (I) belief/reporting stance, (II) continuity ( been being coordinated), and (III) the time frame (“since…”).
· Structure:
· Active (underlying): Subject + has/have been + V-ing + object (since + time).
· Passive (perfect continuous): Object + has/have been being + V³ (+ by + agent).
· With reporting verb (believe) in raising pattern: NP (object) are/is believed to + (perfect continuous passive).
· Examples:
· Active: They believe the team has been building the prototype since 2020.
· Passive: The prototype is believed to have been being built by the team since 2020.
Why other options are incorrect:
· (a) are believed to being have coordinated – wrong word order and forms (“to being have coordinated” is ungrammatical).
· (b) are being coordinated… – drops “believed” and changes the tense/aspect; also mismatches “since the early stages” which prefers perfect aspect.
· (d) are believed to have been coordinated… – loses the continuous aspect (been being), implying completion rather than ongoing coordination.
· Information booster (Perfect Continuous Passive):
· Present perfect continuous passive = has/have + been + being + V³. Though stylistically heavy, it is grammatically valid when you must preserve ongoing action from an earlier time up to (or near) the present.