【C18】A．favorableB．preferableC．desirableD．beneficial

【C18】A．onB．beforeC．atD．in

【C18】A．merelyB．alwaysC．mainlyD．almost

【C18】A．illegalB．oddC．vainD．wrong

【C18】A．atB．toC．inD．of

【C18】A．thatB．whichC．whatD．／

With the constant change of conditions, the outcome is not always______.A．favorableB．reaso