For all the remaining items the stated dates of delivery are approximate, but ______ would these dates be exceeded by more than ten days.

A．in no case

B．in any case

C．under any circumstances

D．by all means

设α₁，α₂．…，α_n均为n维向量，下列结论不正确的是______．

A．若对于任意一组不全为零的数k₁，k₂，…，k_s，都有k₁α₁+k₂α₂+…+k_sα_s≠0，则α₁，α₂，…，α_n线性无关

B．若α₁，α₂，…，α_s线性相关，则对于任意一组不全为零的数k₁，k₂，…，k_s，有k₁α₁+k₂α₂+…+k_sα_s=0

C．α₁，α₂，…，α_s线性无关的充分必要条件是此向量组的秩为s

D．α₁，α₂，…，α_s线性无关的必要条件是其中任意两个向量线性无关