After big rise, pound to pause around $1.35, options markets suggest

LONDON (Reuters) - Having enjoyed a 2% surge on Friday following Boris Johnson's thumping election win, sterling may have to pause for breath, with derivatives markets implying the currency will struggle to rise beyond $1.35 in the next few months.The British prime minister's victory gives him a clear mandate to take Britain out of the European Union by the Jan. 31 deadline, raising hopes the country can draw a line under three years of political chaos that has stymied investment and hobbled..