sCiEntists ArE lEArning morE ABout our nEED For slEEp. most pEoplE slEEp{{u}} (26) {{/u}}Eight hours EACh night.{{u}} (27) {{/u}}pEoplE slEEp morE thAn{{u}} (28) {{/u}}AnD othErs slEEp As{{u}} (29) {{/u}}As two or thrEE hours EACh night. sCiEntists Do not know ExACtly{{u}} (30) {{/u}}somE pEoplE slEEp morE thAn othErs.Dr.ErnEst hArtmAn hAs A (An){{u}} (31) {{/u}}ABout this. hE BEliEvEs thAt thE{{u}} (32) {{/u}}oF slEEp DEpEnDs on how A pErson{{u}} (33) {{/u}}proBlEms. hE sAiD pEoplE who nEED only A FEw{{u}} (34) {{/u}}slEEp usuAlly ArE pEoplE who hAvE muCh EnErgy AnD mAkE gooD usE oF{{u}} (35) {{/u}}to gEt thEir work to BE DonE quiCkly.{{u}} (36) {{/u}}hE sAiD mAny pEoplE who slEEp longEr thAn normAl Do CrEAtivE work AnD sEEm to nEED{{u}} (37) {{/u}}DrEAming timE to FinD solution{{u}} (38) {{/u}}EmotionAl proBlEms. somE sCiEntists AgrEE{{u}} (39) {{/u}}this iDEA AnD othErs DisputE. to DEtErminE thE{{u}} (40) {{/u}}oF thE lACk oF slEEp, sCiEntists hAvE put{{u}} (41) {{/u}}through A sEt oF psyChologiCAl AnD pErFormAnCE tEsts{{u}} (42) {{/u}}thEm, For instAnCE, to ADD Columns oF numBErs or rECitE A pAssAgE rEAD to thEm only minutEs EArliEr, "wE’vE FounD thAt iF you’rE in slEEp{{u}} (43) {{/u}}, pErFormAnCE suFFErs," sAysDr.DAviD、"short-tErm mEmory is{{u}} (44) {{/u}},{{u}} (45) {{/u}}ArE ABilitiEs to mAkE DECisions AnD to ConCEntrAtE."

A．othEr
B．mAny
C．thE othEr
D．somE