Exam ATM topic 2 question 13 discussion

Actual exam question from ISTQB's ATM

Question #: 13
Topic #: 2

You are estimating the effort for the integration testing activities of a new project. Consider the following factors, which can affect that estimation:
I. Availability of re-usable test systems and documentation from previous, similar projects
II. Unexpected timing of components arrival
III. Stability of the integration test team (no turnover)
IV. Many and geographically distributed sub-teams
Which of the following statements is true?

A. I. and II. can negatively affect the estimation III. and IV. usually favor the accuracy of the estimation effort
B. II. and III. can negatively affect the estimation
C. and IV. usually favor the accuracy of the estimation effort
D. II. and IV. can negatively affect the estimation
E. and III. usually favor the accuracy of the estimation effort
F. III. and IV. can negatively affect the estimation
G. and II. usually favor the accuracy of the estimation effort