Most employees in thecomputer industry move from companytocompany,changing jobs several times intheirareers. However,SummitComputers is known throughout the industry forretaining its employees.Summitreedits itssuccess inretaining employees to its informal, nonhierarchical workenvironment.
Whichofthe following,iftrue, most stronglysupports Summit'sexplanationofits success inretaining employees?
(A)Some people employed in the computer industry change jobsifthey become bored with their current projects.
(B)Ahierarchical work environment hindersthecooperative exchange of ideas that computer industry employees consider necessaryfor their work.
(C)Manyof Summit's senior employees had previouslyworkedatonly one othercomputer company.
(D)In a nonhierarchical work environment ,people avoidbehaviorthatmight threaten group harmony and thus avoid discussingwith their colleaguesany dissatisfactiontheymighthavewiththeir jobs.
(E)The cost of livingnear Summitis relatively low comparedtoareas in which someother computer companies
arelocated.
B supports S's explanation directly, D supports S's explanation indirectly.
Why does the answer choose B ,but not D ? | 
