All of these options are the preterite form of the verb leer in Spanish. Here is how it is conjugated: 1. yo leí 1. nosotros leímos 2. tú leíste 2. vosotros leísteis 3. él/ella/Ud. leyó 3. ellos/ellas/Uds. ley<span>eron
You need the third person singular, which is he, or </span>él in Spanish. So, the correct form for that person is leyó. Thus the correct answer is No leyó las señales.
