Though the government encourages foreign investment, (      ) investors are reluctant to commit funds in the current climate situation in the country.

A．Aspiration is a distinctive feature
B．Voicing is a distinctive phonetic feature
C．Nasalization of vowels gives rise to another vowel
D．Length of vowels differentiates one vowel from the other

A．Voiced
B．Voiceless
C．Bilabial
D．Dental