I think (and I hope) that AABH is right. In the checklist mentioned (cicDOTgcDOTca/english/pdf/kits/forms/IMM5690E.pdf) says: "Since July 1, 2012, most applicants to Provincial/Territorial Nominee classes in semi or low-skilled professions that fall under National Occupation Classification (NOC) skill level C and D are required to complete a language proficiency test from one of the following designated agencies:".
Besides, here (cicDOTgcDOTca/english/resources/tools/language/pnp.asp), it says "The monthly nomination spreadsheet submitted to the Centralized Intake Office (CIO) in Sydney, Nova Scotia by Provinces and Territories (PTs) has been updated, and starting in July 2012, will contain a new column titled “Test required?”
When the Centralized Intake Office reviews each NOC C and D Provincial Nominee Program application for completeness, they will use the “Test required?” column in the nomination spreadsheet to determine whether valid language test results should be included in the application.
The following explains when an applicant must include a language assessment with their application and what to do if it is required and not included:
If the province or territory selected “yes” in the “Test required”, then the applicant must include a copy of the language test with their application in addition to all other documents listed in the document checklist for Provincial Nominee Program applicants, in order for it to be considered a complete application.
If an application for permanent residence for which a PT selected “yes” in the “Test Required?” column does not include a copy of valid language test results, then the application will be considered incomplete and the Central Intake Office will return the entire application package to the applicant.
If the province or territory selected “no” in the “Test Required”, then the province or territory has determined that the applicant meets one of the exceptions and the applicant is not required to include a copy of language test results with their application for permanent residence."
To me, the text above, along with the specific wording in the Document Checklist is quite conclusive. Also, and I think is determinant, note that they talk about a Language Benchmark of 4 for NOCs C & D, but there is no minimum Language Benchmark specified for NOCs 0, A or B, which would not make much sense.