All skills listed in an entry are class skills

The "Reading the Monster Entries" section of the SRD states (emphasis mine):

Skills

 

This line gives the creature’s skills, along with each skill’s modifier (including adjustments for ability scores, armor check penalties, and any bonuses from feats or racial traits). All listed skills are class skills, unless the creature has a character class (noted in the entry). A creature’s type and Intelligence score determine the number of skill points it has.

Racial/"type" hit dice don't have class skill lists. Any skill taken with those points is considered a class skill for those HD and grants a full rank.

This is one of those things that notably changed in Pathfinder, where the skill/class skill system works a bit differently and "type" HD do have an associated "class" skill list (as can be seen on this table).

All skills listed in an entry are class skills

The "Reading the Monster Entries" section of the SRD states (emphasis mine):

Skills

This line gives the creature’s skills, along with each skill’s modifier (including adjustments for ability scores, armor check penalties, and any bonuses from feats or racial traits). All listed skills are class skills, unless the creature has a character class (noted in the entry). A creature’s type and Intelligence score determine the number of skill points it has.

Racial/"type" hit dice don't have class skill lists. Any skill taken with those points is considered a class skill for those HD and grants a full rank.

This is one of those things that notably changed in Pathfinder, where the skill/class skill system works a bit differently and "type" HD do have an associated "class" skill list (as can be seen on this table).