Which is the correct target guideline for the single-point fault metric (SPFM) required for ASIL D?

Answer: C. 99% or higher

SPFM indicates how few of the safety-related faults are single-point faults, which by themselves lead to violation of a safety goal, or residual faults, which remain undetected by safety mechanisms; it is calculated as 1 minus the proportion of their combined failure rate. Target guidelines are 90% or higher for ASIL B, 97% or higher for ASIL C and 99% or higher for ASIL D. The latent fault metric (LFM) guidelines are 60% or higher for ASIL B, 80% or higher for ASIL C and 90% or higher for ASIL D, so 90% and 60% are easily confused with LFM or ASIL B values.