下列离子方程式，书写正确的是 [ ]

A．硫酸氢钠溶液与NaOH溶液混合：HSO₄^-+ OH^-= H₂O + SO₄^2-

B．石灰石溶于硝酸：CO₃^2- + 2H⁺ = H₂O + CO₂↑

C．少量CO₂通入澄清石灰水中:CO₂+Ca²⁺ +2OH^-=CaCO₃↓+H₂O

D．碳酸镁跟硫酸反应：MgCO₃+2H⁺=Mg²⁺+H₂O+CO₂↑

The nobler and more perfect a thing is, the later and slower it is becoming mature. A man reaches the mature (1) of his reasoning powers and mental faculties (2) before the age of twenty-eight; a woman at eighteen. And then, too, in the case of woman, it is the only reason of a sort--very mean in its (3) . That is why women remain children their whole life long; never seeing (4) but what is quite close to them, (5) fast to the present moment, taking appearance for (6) , and preferring (7) to matters of the first importance. For it is (8) his reasoning faculty that man does not live in the present only, (9) the brute, but looks about him and considers the past and the future; and this is the origin of (10) , as well as that of care and anxiety which so many people (11) Both the advantages and the disadvantages, which this (12) , are (13) in by the woman to a smaller extent because of her weaker power of reasoning. She may, in fact, be described as intellectually shortsighted, (14) , while she has an immediate understanding of what lies quite close to her, her field of (15) is narrow and does not reach to what is (16) ; so that things which are absent, or past, or to come, have much less effect upon women than upon men. This is the reason why women are inclined to be (17) and sometimes carry their desire to a (18) that borders upon madness. In their hearts, women think it is men’s business to earn money and theirs to spend it--if possible during their husband’s life, (19) , at any rate, after his death. The very fact that their husband hands them (20) his earnings for purposes of housekeeping strengthens them in this belief.

15（）

A.sigh

B.vision

C.reach

D.glance