'Toinvestigate,toimprove,tostudycarefully,todecideto'ispreferrableto'tomakeaninvestigationof,tomakeanimprovement,tomakeacarefulstudy,tomakeadecision'inwriting.

Read the report. Then, choose the correct answers.What isthe purpose of the report? A: to createbetter rail yard safety conditions B: tosuggest improvements to safety features C: torecommend better railroad maintenance D: toinvestigate an accident and help avoid a repeat