Which of the following metals is in liquid state at normal room temperature?

Francium, cesium, gallium, and rubidium are four elements that melt at temperatures slightly higher than room temperature. Francium (symbol Fr and atomic number 87), a radioactive and reactive metal, melts around 300 K. Francium is the most electropositive of all the elements. Cesium (symbol Cs and atomic number 55), a soft metal that violently reacts with water, melts at 301.59 K. The low melting point and softness of francium and cesium are a consequence of the size of their atoms. In fact, cesium atoms are larger than those of any other element. Gallium (symbol Ga and atomic number 31), a grayish metal, melts at 303.3 K. Gallium can be melted by body temperature, as in a gloved hand. Rubidium (symbol Rb and atomic number 37) is soft, silvery-white reactive metal, with a melting point of 312.46 K. Rubidium spontaneously ignites to form rubidium oxide. Like cesium, rubidium reacts violently with water.