The highlighted word above (The New Paper, 14 April 2010) should, of course, be cost rather than cause. As with so many typos, this one seems to have a phonological basis.
But how do cost and cause end up as homophones (or at best near-homophones) in Singapore English when, in British Received Pronunciation (RP) for example, they are /kɒst/ and /kɔ:z/?
The first factor is the neutralization of distinctions between vowels that are differentiated in other varieties of English: here, the distinction between short /ɒ/ and long /ɔ:/, which is responsible for pot/port being a minimal pair in RP.
The second is the phenomenon of final fricative devoicing, where /z/ becomes [s], which leads to course and cause being /kɒs/ or /kɔ:s/ in Singapore English, whereas in RP they are /kɔ:s/ and /kɔ:z/.
And finally, the simplication of consonant clusters, leading to the loss of /t/ in cost.