will, validity of No will shall be valid unless-(a) it is in writing, and signed by the testator, or by some other person in his presence and by his direction; and (b) it appears that the testator intended by his signature to give effect to the will; and (c) the signature is made or acknowledged by the testator in the presence of two or more witnesses present at the same time; and (d) each witness either (i) attests and signs the will; or (ii) acknowledges his signature, in the presence of the testator (but not necessarily in the presence of any other witness), but no form of attestation shall be necessary.