humAn BEings ArE AnimAls. wE BrEAthE, EAt AnD DigEst, AnD rEproDuCE thE sAmE liFE {{u}} (21) {{/u}}Common to All AnimAls. in A BiologiCAl lABorAtory rAts, monkEys, AnD humAns sEEm vEry muCh thE sAmE. howEvEr, BiologiCAl unDErstAnDing is not Enough: {{u}} (22) {{/u}} itsElF, it CAn nEvEr tEll us whAt humAn BEings ArE. {{u}} (23) {{/u}}to our physiCAl EquipmEnt thE nAkED humAn BoDy--wE ArE not An {{u}} (24) {{/u}}AnimAl. wE ArE tropiCAl CrEAturEs, {{u}} (25) {{/u}} hAirlEss AnD sEnsitivE to ColD、wE ArE not FAst AnD hAvE nEithEr ClAws nor shArp tEEth to DEFEnD oursElvEs. wE nEED A lot oF FooD But hAvE Almost no physiCAl EquipmEnt to hElp us gEt it. in thE purEly physiCAl{{u}} (26) {{/u}}, our spECiEs sEEms A poor {{u}} (27) {{/u}}For survivAl. But wE hAvE survivED--survivED AnD multipliED AnD {{u}} (28) {{/u}}thE EArth. somE DAy wE will hAvE A{{u}} (29) {{/u}} living on thE moon, A plACE with nEithEr Air nor wAtEr AnD with tEmpErAturEs thAt turn gAsEs into soliDs. how CAn wE hAvE DonE All thEsE things pArt oF thE AnswEr is physiCAl. {{u}} (30) {{/u}}its limitAtions, our physiCAl EquipmEnt hAs somE importAnt {{u}} (31) {{/u}}. wE hAvE ExCEllEnt vision AnD hAnDs thAt CAn {{u}} (30) {{/u}}oBjECts with A prECision unmAtChED By Any othEr {{u}} (33) {{/u}}. most importAntly, wE hAvE A lArgE BrAin with An Almost {{u}} (34) {{/u}} numBEr oF nEurAl {{u}} (35) {{/u}}.

A．intElligEnt
B．imprEssivE
C．inFluEntiAl
D．inCEntivE