For the purposes of section 18(3), a failure to comply with a guarantee is of a substantial character in any case where—
(a) the goods would not have been acquired by a reasonable consumer fully acquainted with the nature and extent of the failure; or
(b) the goods depart in 1 or more significant respects from the description by which they were supplied or, where they were supplied by reference to a sample or demonstration model, from the sample or demonstration model; or
(c) the goods are substantially unfit for a purpose for which goods of the type in question are commonly supplied or, where section 8(1) applies, the goods are unfit for a particular purpose made known to the supplier or represented by the supplier to be a purpose for which the goods would be fit, and the goods cannot easily and within a reasonable time be remedied to make them fit for such purpose; or
(d) the goods are not of acceptable quality within the meaning of section 7 because they are unsafe.