对于度量绩效域，有效的度量指标应该具备（）SMART特征。
A． Specific、Measurable、Attainable、Relevant、Time - bount
B． Strategic、Measurable、Achievable、Realistic、Time-bound
C． Specific、Measurable、Actionable、Relevant、Time-bound
D． Specific、Meaningful、Achievable、Relevant、Timely